Chemical composition and bioactive compounds of Cucurbitaceae seeds: Potential sources for new trends of plant oils

Keywords: Cucurbitaceae seeds; Cold pressed seeds; Seed oils; Fatty acids; Sterols; Phenolic 
Compounds. 
1. Introduction 
Pumpkin, watermelon, and melon fruits are consumed in natura or in their processed 
forms as purees, jams, juices, nectars, fruit cocktails, and alcoholic beverages (Veronezi and 
Jorge, 2018; Rezig et al., 2012; Wani et al., 2011a). In the process of fruit manufacturing, 
large amounts of waste, such as peels and seeds, are discarded (Veronezi and Jorge, 2018; 
Mallek-Ayadi et al., 2018; Veronezi and Jorge, 2015). Moreover, the high costs of drying, 
storage and transportation of these byproducts are economically unprofitable. 
In recent years, fruit seeds have received growing interest due to the important 
nutritional and medicinal properties of their bioactive components. Hence, fruit seeds can be 
used for the extraction of plant oils, which contain a great number of valuable biocomponents 
and natural antioxidants (Mallek-Ayadi et al., 2017). 
Pumpkin (Cucurbita pepo), watermelon (Citrullus lanatus), and melon (Cucumis 
melo) belong to the Cucurbitaceae family, also referred to as cucurbits which is a medium-
sized plant family growing extensively in temperate, tropical and subtropical regions of the 
world. 
Pumpkin seeds are used in culinary practices mainly in the southern parts of Austria, 
Slovenia, and Hungary (Murković et al., 1996). They are similarly consumed after being 
ACCEPTED MANUSCRIPT

---

3 
salted and roasted in North African countries, mainly in Tunisia. Pumpkin seed oil was 
reported to possess a strong antioxidant potential and has been identified as an exceptional 
preventive against hypertension and carcinogenic diseases (Rezig et al., 2012).
Watermelon seeds, for instance have also been reported to be an excellent source of 
dietary oil (Wani et al., 2011b). These seeds are first dried, then used in various forms, such 
as snacks in India and Arabian and African countries, as an additive in various dishes, for 
decorating cakes and as a stuffing in indigenous kheer (Wani et al., 2011a).
Moreover, melon seeds are directly consumed in Tunisia and in African countries as 
snacks. They are also said to have favourable medicinal properties and are used to treat 
chronic or acute eczema (Teotia and Ramakrishna, 1984). The kernels are also used in 
sweetmeats and toppings as a substitute for almonds and pistachios in India (Wani et al., 
2011a). 
However, few studies were conducted in characterizing the chemical composition of 
Cucurbitaceae seeds and investigating the bioactive compounds of Cucurbitaceae seed oils. 
Given these facts, the purpose of this work is to study the chemical composition of 
pumpkin, watermelon, and melon seeds and seed oils cultivated in Tunisia, in order to 
evaluate the potential of these seeds as special oils sources.